#top{
    width: 700px;
    height: 153px;

    float: left;
    margin-bottom: 2px;
}
#banner{
    background: url(./img/banner.jpg);
    width: 700px;
    height: 120px;
}
#nav li{
    width: 100px;
    text-align: center;
    line-height: 33px;
}
#nav a{
    background: url(./img/button1.jpg ) no-repeat;
    display: block;

}
#nav a:hover{
    background: url(./img/button1_bg.jpg);
}
